As many as one in three home purchases fall through for one reason or another. While this can be very frustrating, there is nothing you can do about it if contracts have not been exchanged.In England and Wales, an offer to purchase a property is not legally binding. This means the buyer or seller can change their mind and pull out at any time before contracts are exchanged without penalty. This can happen weeks, or even months, into the process, and can leave both parties significantly out of pocket.